i didn't know about c graphics,unix,linux.but with my knowledge i want to do a project.can i ?

Forget about doing any projects for now -- juist concentrate your efforts on learning the language. You can read books (see your local library for free copies), get online e-books, or read links in the Read Me threads at the top of this and the C++ board.

Hey, if you so much want something to do... In my GTK Asteroids http://www.daniweb.com/code/snippet744.html i notice that the enemy bullet sometimeas goes through the ship (i didn't notice any other object to anyhow cross without collision). It's very rare, and harldy ever a big problem in the game, but it sometimes happens... I don't know whether there was a bug in the collision detection in the original version, or i spoiled something with my clumsy hand, but the bugs and fixing them is inevitably a reality in the programming. This is a quite simple game, and doing it wouldn't likely be very difficult. But if you would be able to fix it, then you know already something about programming :)